Lifting device for motor and other vehicles



06t- 2, 1934- A. l. LOGETTE `ET Al. 41,975,551

LIFTING DEVICE FOR MOTOR AND OTHER VEHICLES Filed Oct. 1l. 1932 Patented Get. 2, 1934 stares PATT FFICE Abraham Isaac Logette and Edgar Harry Daintcn, London, England Application October 11, 1932, Serial No. 637,340

In Great Britain October 15, 1%1

1 Claim. (Cl. 251-93) This invention relates to fluid pressure lifting devices for vehicles of the kind comprising a lifting frame or platform that is mounted upon the head of a tubular ram arranged in operable corn- '75 bination with a pressure cylinder housed below ground level and connected to a source of uid pressure so that the ram can be operated to raise from'and return to ground level, the lifting frame or platform together with the vehicle carried thereon.

The object cf the present invention is to improve and simplify the construction and arrangement ofv such lifting devices so as to considerably reduce the cost of production and maintenance,

y`15^while increasing the convenience and efficiency thereof.

According to this invention, in a fluid pressure lifting device of the kind referred to, the head of the tubular lifting ram forms an internalpres- '.2Qsure chamber that is connected by a tube to the interior of the ram or pressure cylinder, in which latter oilV or other suitable non-elastic iiuid is stored, while the pressure cylinder: is closed and is'connected at its upper end to an air compressor '251er the like through suitable controls, so vthat on admitting compressed air to the upper end of the closed pressure cylinder the oil stored therein is driven through the connecting pipe or tube into the pressure chamber formed by the head of the tubular ram, thus raising the ram together with the lifting frame or platform carried thereby, the

lowering'of the ram and lifting platform being effected by releasing the compressed air from the rain cylinder so as to allow the displaced oil to .return thereto from the tubular ram as the latter sinks under the influence of the load.

VIn a convenient construction the tubular ram is adapted to work fluid tight over the exteriorcf a-vertically disposed pressure cylinder which is '40lclosed at its upper and lower ends and forms the reservoir for the oil or other inelastic fluid, while the head of the tubular ram is closed and projects beyond the closed Lipper end of the pressure cylinder so vas to form a pressure chamber above the closed upper end of the pressure cylinder.

The closedpressure cylinder is connected above Y the maximum level of the oil or the like stored therein to an air compressor through suitable controls, while the pressure chamber formed by 50 the closed head of the tubular ram is connected to the interior of the pressure cylinder by a tube which is secured in the upper end of such cylinder and extends to the lower end thereof so that on admission of compressed air to the pressure cylinl:1der the oil stored therein is forced into the pressure chamber formed by the closed upper end of the ram through the depending tube With a Siphon-like action, thus raising the ram together with the lifting platform carried thereby.

On releasing the compressed air from the pressure cylinder the displaced oil returns from the tubular ram by the depending tube to its normal position in the cylinder as the ram returns under the iniiuence of gravity.

The interior'of the tubular ram works fluid tight over the closed upper end of the pressure cylinder, which end is furnished with a cup leather or the like to form a sliding fluid tight joint with the interior surface of the tubular ram, While the lower end of the latter is furnished with an annular guide which makes a sliding iit with the exterior surface of the pressure cylinder and also forms an abutment which engages a stop ring mounted upon the exterior of the pressure cylinder, when ther tubular ram reaches the klimit of its lift.

The invention is illustrated by Way of example in the accompanying drawing, wherein similar references indicate like parts.

Fig. l is a vertical sectional view of a uid pres- .ire lifting device constructed in accordance with the present invention showing the ram lowered, and Fig. 2 a cross section on the line 2 2.

As shown in the drawing the ram pit l is lined with a sheet metal casing 2 which rests upon concrete footing 3 while 4 indicates a tubular guide which is formed with external anges 5 and 5a and is secured in the upper end of the Aram pit by means of bolts 6 which pass through perfcrations in the 1 flange 5, while the flange 5a serves to hold the guide co-axial with the ram pit.

The pressure cylinder 7 is closed at'its lower end by a plate 8 and at its upper end by a partiticn 12 and is disposed vertically in the ram pit co-axially with the tubular guide 4. The plate 8 is adapted to t into the lower end of the pressure cylinder in which it is Welded or otherwise secured fluid tight. l

Such plate is formed with an annular flange 9 and has a centrally disposed convex boss l()A formed on the lower surface thereof. The flange 9 is slotted as indicated at 9a so as to engage pins 1l secured in the bottom of the ram pit and thus prevent relative rotation of the pressure v cylinder '7, while the boss 10 forms a footstep bearing for the pressure cylinder and serves to compensate for slight variations of level in the bottom of the ram pit so as to maintain the pressure cylinder co-axial with the guide 4.

The plate or partition 12 is welded or otherwise secured iiuid tight on the upper end of the pressure cylinder 7 and has a slightly greater diameter than the pressure cylinder so as to form an exterior flange 12a thereon.

Such plate is centrally perforated to accommodate a vertically disposed open tube 13 which is secured therein in any convenient manner so that one end of such tube extends near to the bottom of the pressure cylinder, while its other end projects beyond the top closure plate 12 thereof.

A second vertically disposed tube 14 is mounted in the interior of the pressure cylinder 7, the upper end of such tube extending near to the under side of the top closure plate 12, while its lower end passes through a perforation near the lower end of the pressure cylinder and is screwed or otherwise secured in an elbow 15 welded or otherwise secured to the exterior of the pressure cylinder' and is connected by a pipe 15a to a source of compressed air such as a compressor, not shown. Y

The tubular ram 16 is mounted upon the exterior of the pressure cylinder 7, its inner surface making a sliding t with the iiange 12a, while the outer surface of such ram makes a sliding ilt with the tubular guide i and works through a gland 17 and packing 17d which are secured in a stuifing box 18 formed by a recess in the tubular guide 4.

The lower end of the tubular ram 16 is provided with an annular guide 19 which makes a sliding t with the exterior of the pressure cylinder and forms an abutment 19a. which abuts a stop ring 20 welded or otherwise secured to the exterior of the pressure cylinder l near the upper end thereof when the ram 15 reaches the lil/nit of its lift.

A uid tight connection is made between the inner surface of the tubular rain 16 and the flange 12d at the upper end of the pressure cylinder by means of a cup leather or the like 2l which is secured by means of an annular washer 22 and studs 23 to the upper surface of the closure plate l2 in which is formed a priming and filling hole that is closed by a screw plug or stud 25.

The head 16a of the tubular ram projects beyond the top closiue plate 12 of the pressure cylinder so as to enclose the upper end of the tube 13 and is closed fluid tight by a cover plate 26 so as to form a pressure chamber above the pressure cylinder 7.

As shown, the cover plate 26 is grooved on its under surface to receive the edge of the tubular ram together with a suitable packing and is made of larger diameter than the ram so that when assembled to the latter it forms a ange 26a in which perforations are formed to receive a series of screw studs 27 by means of which the cover plate is secured in position.

The studs 27 engage with tapped holes formed in ene of a pair of centraily perforated rectangular plates 28 that are welded or otherwise secured in spaced relationship on the exterior of the head 16a of the ram so as to enable a suitable lifting frame or platform to be readily secured thereto, while the cover plate 26 is furnished with a suitable priming valve or plug 31.

As indicated, the lifting frame or platform comprises parallel I-section girders 30 which are arranged one on each side of the ram head between the plates 28, to which latter the girders 30 are riveted, bolted or otherwise rmly secured.

The girders 30, as shown, constitute the longitudinal members of a run-over type of platform, in which case such girders are secured symmetrically between the plates 2S so that the ram head is located centrally of the lifting frame or platform in which such girders are comprised.

Alternatively, the girders may constitute the central members of a run-on type of lifting frame or platform, the longitudinal members of which are carried by the opposite ends of the central girders 30.

As shown, the air pipe 15a runs through slots formed in the anges 5 and 5a of the tubular guide 4, and is run through a trench 32 to an air compressor or other suitable source of compressed air, not shown. Oil or other suitable non-elastic motive fluid is introduced into the pressure cylinder through the aperture in the top closure plate 12 so as to leave an air space in the upper end of the pressure cylinder into which the upper end of the air pipe le projects, as indicated.

On admitting compressed air at suitable pressure to the upper end of the cylinder through the air pipe 14 the oil or other liquid stored in the pressure cylinder is forced through the pipe 13 into the pressure chamber formed by the head of the ram, thus raising the latter together with the lifting platform attached thereto until the abutment on the lower end of the ram bears against the stop ring 20 on the exterior of the pressure cylinder.

On releasing the compressed air from the pressure cylinder the oil returns through the pipe 13 from the upper end of the raised tubular ram to the pressure cylinder as the ram returns under the influence of gravity.

What we claim is:-

A fluid pressure lifting device comprising a vertically disposed pressure cylinder closed at both ends and adapted to form a reservoir for inelastic motive fluid, a depending siphon tube therein which projects beyond the closed head of said cylinder and is connected thereto above the maximum level of the inelastic motive fluid stored in said reservoir, a source of compressed air communicating with said pressure cylinder, a tubular ram adapted to work fluid tight over the exterior of said pressure cylinder, the head of said ram being closed and projecting beyond the closed head of the pressure cylinder to form a pressure chamber that is connected to the interior of the pressure cylinder by the siphon tube, the projecting head of said ram being adapted to carry a lifting frame furnished with trackways for carrying a vehicle, the vertically disposed pressure cylinder being housed in a pit, and provided with a plate formed with a spherical self-centering footstep bearing for said cylinder, while its upper end is provided with a plate adapted to form an external flange and is furnished with a cup leather over which the tubular ram works fluid tight, the lower end of the ram being furnished with an annular guide that works over the exterior of the pressure cylinder, the latter carrying a stop ring against which the guide abuts when the ram reaches the limit of the lift.

ABRAHAM ISAAC LOGETTE. EDGAR HARRY DAINTON. 

